Abstract

Collapsible soil is known as problematic soil, which possesses considerable strength when it is dry and loses its strength and experience excessive settlement when inundated. Geotechnical engineers face a great challenge when they build on/in collapsible soil. Inundation of collapsible soil may take place due to surface running water or raising the groundwater level. In case of surface water, the amount of settlement varies, depending on the extent of the wetting zone and the degree of saturation in the soil. The case of rising groundwater will produce full saturation in the ground and accordingly, the maximum settlement of the foundations. In the literature, there is lack of sufficient and reliable methods for predicting drag force on piles embedded in collapsible soils. These difficulties stem from the fact modeling collapsible soil analytically is difficult at best, while collapsible soil is governed by the collapse potential of the soil and method of inundation. In this thesis, the results of an experimental investigation on a single end-bearing pile embedded in collapsible soil will be presented. The objective of this experimental investigation was to measure the soil collapse and the associated settlement and accordingly the negative skin friction on the pile's shaft for a given soil and pile conditions due to soil inundation. Empirical formula is presented to estimate the negative skin friction on these piles for a given soil/pile condition.